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Joined: Sep 2005
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CT, its a peaker in Aurora Il. it wasn't unnoticed, ....it was ignored !!!
Tom
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Joined: Jun 2004
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togol
How I envy you.
I never have great stories to tell.
The best I can do is recount some semi-suicidal apprentice boner; and none of them would be news to anyone.
I am pleased no one was hurt.
It seems that some sort of LOTO breakdown occured.
Tesla
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Joined: Oct 2004
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togol: Thank you for the clarification. So if I read it correctly the fireball was coming from the damaged cabinet.... I would have probably changed careers after such an event, since I've seen and heard many incidents which make me very cautious around any electrical gear. To still have such vivid memories after four years... Truly a miracle no one was hurt, indeed. But I imagine that like you, they still have effects from that day. A bit OT here: BTW, in the thread "what do you look like?" was that switch in the pic at the same facility? I'll bet the "bark" from the "B" phase was a pucker-inducer as well. Here's the link: https://www.electrical-contractor.net/ubb/Forum1/HTML/002850-7.html My very first exposure to that kind of horrible sound was when as a kid, I was bicycling past a pole with a transformer when it got hit by lightning. The concussion knocked me clean off my bike and the arc's noise gave me nightmares for months. But it did later reinforce my interest in all things electrical. Edited to add link for your viewing pleasure... [This message has been edited by mxslick (edited 10-08-2005).]
Stupid should be painful.
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Joined: Sep 2005
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Tesla, it WAS a once in a lifetime event ,that's for sure.....
.. a bit more explanation, that damaged building is where ALL of the LOTO for the plant power is done,in other words , the tranformers 4160V output can be isolated in that building, but the 138Kv feeds for it are either from the generator ,or a backfeed from the utlity thru the MPT.
normally, opening the gen. breaker and the airswitch isloates the primary and a breaker in the building isolates the secondary
Tom
[This message has been edited by togol (edited 10-07-2005).]
Tom
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Joined: Sep 2005
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mxslick, yes that is the same job, taken in Spring that year, ironically, I had to get a butt chewin' ....by the SAME engineer who was running the test that led to the fire....., about damaging the switch in my photo
Tom
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Joined: Oct 2004
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Sounds to me like that "engineer" is the one in need of a serious butt chewing, at least. After this incident that chap would never work on any project I owned for sure.
Chews you out for opening a switch? Bet ya the "fault" on "B" phase was due to him in one way or another.......
Stupid should be painful.
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Joined: Dec 2000
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See more pics Here [This message has been edited by electure (edited 10-22-2005).]
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Joined: Apr 2003
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Togol, thanks for sharing your experiences with this. I work in a power plant and frequently do the switching in the high voltage rack and appreciate how very lucky everyone is to walk away from this one. I have seen a few failures, but thankfully nothing of this magnitude, and nothing caused by faulty procedure. Someone must have had to clean out their pants after this one.
One point though, are you missing a decimal point in your voltages? Our generators put out 13.8 Kv, and our primary switchrack uses 34.5 Kv. At first I thought you must have been working with a really large unit, but the numbers just make more sense to me with the decimals.
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Joined: Sep 2005
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CaOperator, at that job everyone involved always referred to the outputs those two units as "345".... while the others were "138 " , the MV was called thirteen eight, or 13.8 . It was, as I recall, a really big deal on the morning that the big line was energized ! The start-up folks wanted EVERYONE to stay in tthe trailers while they brought that it up. Something that wuold not occur with energzing 34.5 Kv
The short answer is that the line was 345Kv. .......I couldn't beleve it either, as it was my first exposure to REALLY high voltage
This plant was plagued with many mis-haps , another ...near-miss...involved that same line, near the end of the construction phase.
After some initial checks .... The Utility opened their switch in their yard and ..following their safety procedure...,pulled a pin out of the mechanical linkage..to prevent an accidental closure.
On our side, they followed LOTO, plus, a thoughtful lineman installed some 4/0 "safety grounds" on the high side of the transformer , at the switch !
Naturally, we experienced some VERY high winds a few days later, which, because of the missing pin, .... and unknown to anyone inside the plant ....,caused the Utility switch to fall closed . energizing the line, but because of the wind , no one could hear it !
Our switch , which was under LOTO in the control room, started to drift closed, until it finally got close enough to those grounded stabs and then BLEW the 4/0 grounds clear which caused a TRIP on the Utility side.... There were men working on the other side of the transformer blast wall when this happened, and while no one was physically injured , there were very many ummm, pissed -off electricians
BTW, the lineman got his butt chewed out for hanging those 4/0 grounds on his own initiative, but his actions prevented a very, very serious catastrophe. as usual , the lineman boss forgot to apologize to the guy afterward togol
Tom
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Joined: Apr 2003
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DRIFTED CLOSED????!!?? I (and several others, lol)would have somebodies butt for that one. What good is a self closing air gap? Our switchrack disconnects ALL have padlocks on them, both in the open and closed positions, if they changed positions accidentally then there has been a serious failure. And hanging grounds requires everyone involved to be notified. It sounds like there were two seperate work authorities issued here and there was no proper written procedures. Even in cases (or perhaps especially) of abnormal conditions we take the time write up a procedure and review it with all parties. I am thankful the agency I work for does not engage in russian roulette switching like that. Again thank goodness you and all others are safe and whole.
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